Electric switch



Dec. 1 1925. l 1,563,854

R. R. HAUGH ELECTRIC SWITCH Filed April 17. 1922 l Ii Patented Dec. 1, 1925.

UNITED STATES RAYMOND B. HAUGH, OF CHICAGO, ILLINOIS.

ELECTRIC SWITCH.

Application filed April 17, 1922. Serial No. 553,854,

To all whom it may concern: 1

Be it known that I, RAYMOND R. HAUGII, a citizen of the United States of America, and a. resident of Chicago, county of Cook, and State of Illinois, have invented a new and useful Improvement in Electric Switches, of which the following is a speciiication.

This invention pertains to improvements in thermostatic switches similar in general character and purpose to the one described in my Patent No. 1,387 ,980, of August-16, 1921, and also to the arrangement ofl the cord and connections therefor in such a switch. These switches are intended for thc control of electric circuits as applied to electrically heated implements, as for instance, flat-irons and cookers or .the like, overheat- Iing of which mi ht be injurious ,to the ini-f plements themsc ves or to the materials or object-s with which they may be associated in use.

The main objects of the invention are to provide a simple automatic switch of improved construction and operation to break the electric circuit when the temperature of the switch reaches av predetermined temperature; to provide a manually operated switch of this sort which will have a. snap open action and also a quick closure action so as not to burn the Contact pointsas usually results from slow opening and closing; to provide the switch with lock closed and lock open devices so as to prevent accidental operation and possible consequent damage; 'and to provide a switch plug device of the character having the supply cord 1netter positioned to a'void injury and confusion in use.

An illustrative embodiment of this invention is shown in the accompanying drawings, in which Figure 1 is a plan of an electric {lat-iron having a plug switch attachmentembodying the invention .hereina-ft er described.

Fig. 2 is an end elevation ofthe device of Figure 1 as viewed from the right.

Fig. 3 is an enlar ed inside face plan of the lower member 0% the two-part plug.

Fig. 4 is a top end view of the plug with.

a part of the casing walls broken away, and with the plug shown with the normally upward face disposed downward.

F ig. 5 is a greatly-enlarged cross section on the line 5--5 of Fig. 3, and shows the composite structure of they thermostatic blade, and the angular position of the handle thereon.

In the construction shownin the drawings, the switch plug 1, which may be formed and adapted for attaching to any one of a number of different 'current consuming devices, is here shown attached to a flat-iron 2, having a handle 2. The member 1 is provided with a current supply cord 3 protruding from one side near ,the top.

The plug l includes a sectional shell or casing in which the switch parts are mounted, said casing consisting of a lower base part 4, and a removable top 0r cover member 5 held in place by a pair of screws l substantially as customary in such devices.

'lhe circuit extending' through the plug 1 includes a pair of terminals 6 and 7, of spring-walled tubular construction4 adapted to provide good electrical connection with thecorresponding contacts, partly shown at 2 on'Fig. l. There is a plate 8 rigidly mounted .on said member 4, for supporting a movable switch blade 9. Another plate 10 is also attached rigidly to member 4 to support the spring contact member 11, which is fastened to plate 10 by screws 12. The plate 10 is set in a slight depression formed to receive said plate in the member 4, and is secured in place by a'screw 13, which may serve also to atta/ch one of the conductorsof cord 3.

The plate 8 is fastened in place' by av pair of screws 14 and v15. nThe switch blade 9 is oscillatably mounted on a pivot pin 16 set in the plate 8, and is urged toward/its open position by a spring 17, one end of which engages the middle part of said blade, and the other end is set in a shoulder 18 turned up on plate 10'. The plate 10 is provided with a square shoulder 19 struck up in a position to retain the blade 9 inits closed position. Another shoulder 20 is struck up on plate Sback of shoulder 19 to serve as a stop for the blade when it snaps open. Medially disposed between theshoulders 19 and 20 is an o der 21, which, though serving to oppose closingv the switch is readily overcome by application of a moderate degree of force on the part of the user, as a result of which vthe blade will snap forward into place in a manner corresponding approximately with the snap open action.

ositely facing inclined shoul- In order that the switchimay snap open automatically at a predetermined temperature, the blade 9 is of composite structure,

and includes a pair of thin flat strips brazed together, said strips having diii'erent coefficience of linear expansion, brass being used on the inner strip 22, and iron for the outer strip 23. A convenient handle 24 yis attached to the projecting outer end of the blade, which handlelis of oblong shape and disposed 'at an angle of about forty-iive de- Aber grees to facilitate and insure proper application of force for manually opening and closing, and especially to insure applying the closure force in a direction to cause a quick snap-like action.-

Referring now to the cord 3, one of the conductors 25 isconnected directly to the plate 10, and the other conductor 26 is connected directly to terminal 6 by means of a screw 27. The other terminal 7' is connected to the plate 8 by means of a spring connector strip 28 secured at one end by a screw 15, and at its other end by screw 29. It is to be noted that the spring clip 11 comprises a pair of arms 30 which may be formed integrally, adapted to embracingly receive the blade 9 as shown in Fig. 4. It is to be understood that plug members 4 and 5 are of insulating material, as, for instance, hard ruband that one of said members is formed with blade 9.. An inletaperture 32 is also provided for the cord 3.

The spring contact or terminal 11 is made of thin flat sheet metal voit' resilient character,

and is adapted to yield for movement transversely of the plane of pivotal movement of the blade 9 to accommodate the necessary thermostatic warping of the latter as it bends upward to release from shoulder 19. Moreover, this member l1 is formed with its outer tip l1 turned upwardly somewhat so as to provide a relative-ly wide mouth to receive the end ring edge of the blade -9 in closing. l

It is to be noted that when the plug is in place on the implement 2, whateverk jars may occur as by setting the iron down quickl or by tilting it backward vto stand on en will tend to urge or throw the switch blade 9 downward toward the casing member 4 the more tightly into place behind the shoulder 19. It is also to be noted that the angular position ofthe handle 24v is such that normal pressureA against the side thereof, as 'indicated by the arrows on Figures 1 and 5, will at first fail to overcome the resist-l ance f the inclined shoulder 21, but as soon as greater pressure is applied and .inclined a little more toward vthe ultimate direction of movement of the blade, it will suddenly slip over to its closed position with a snap-like action substantially like that provided for by the spring 17 in' opening the switch.

a notch 31 to provide for movement of,

Although but one specific embodiment of this invention has been herein shown and described it will be understood that. numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim:

1. An electric switch provided with a thin laminated thermostatic blade, means for normally urging said blade edgewise to its open position, means for holding said blade in closed position, and means for manually operatingsaid blade,v said blade being adapted and arranged to open at a predetermined temperature by warping sidewise to avoid said holding means.

2. An electric switch having a thermostatic blade, a detent for holding said blade in closed position, manually operated means to release said blade from said detent,"said determined temperature, rigid means for.

holding said blade in open position' and manually operated means for. closing said switch against the said holding means.

3. An electric switch device comprising a frame part having an aperture containing a stop and a pair ofcontact members, vone of which is in the form of a thin compound laminated blade of unitary character pivotally mounted at one Aend and provided with`a handle adapted for swinging mainly edgewise into and out of engagement vwith said stop and with the other said contact, the blade member being formed of thermostatic material adapted for sidewise warping to automatic release from said stop at a predetermined temperature.

4. A thermostatic switch comprising a base Vpart and a pair of contactv members, one of which is blade-like and pivotally mounted on said base part for swinging by manual operation into and outof engagel ment with the other contact member also mounted on said base part, said base part having rigid therewith a' shoulder spaced vfrom theswitch pivot and-in the normal path of movement of said blade and disbe warped clear of said shoulder by increase in temperature.

5. A biased thermostatic switch of the character described having a resilient blade and a pair of positive stops Vin the normal path of said-blade', one to limit its degree of opening and the other to squarely resist its opening, and also an inclined stop to appreciably oppose closure of said blade, said y blade 'being formed and adapted for normal edgewise movement to open and close, and

being transversely yielding and responsive to `warping either thermostatically or manually, said blade havin an inclined handle to insure proper manua operation.

6. A thermostatic switch comprising. a base part and a pair of contact members, one of which is blade-like and pivotally mounted on said base part for swinging manually edgewise into and out of engagement with the other contact member which is also mounted on said base part, said base part having rigidly mounted thereon a shoulder spaced from the switch pivot and in the normal path of movement of the blade and disposed to normally hold the switch closed, said blade being resilient so that it may be sprung manually sidewise clear of said shoulder and also being of thermostatic material so as to be Warped clear of said shoulder by increase in temperature, said blade having a attish handle set at an angle to the plane of said blade.

7. In a biased switch a stop in combination with a laminated blade constructed to Warp thermostatically transversely to its opening and closing movement to pass said stop.

8. A switch including a pair of terminals, a thermostatic blade pivoted to one of said terminals and arranged to swing into and out of engagement with the other said terminal, said blade being constructed to warp crossWiSe of its pivotal movement responsive to temperature change, and said other terminal being resilient and yielding in the same direction to accommodate such Warping when the switch is closed.

Signed at Chicago this 13th day of April,

RAYMOND R. HAUGH. 

